Catch 22
by whithertits
Summary: Castiel is determined to make Dean his mate.  Non-con, knotting, spoilers for 6x22.  Castiel/Dean, Sam/Dean.
1. Chapter 1

**Warnings**: non-con, animal traits (knotting), post 6x22, kidnapping, bondage and torture, potential future mpreg

***  
>Sam woke to the sudden <em>whoosh<em> of displaced air. He blinked and didn't move, eyes slowly tracking over his surroundings. He was sprawled out in a cell, one arm stretched out in front of him and blocking his view. What he could see sent his heart pumping: cold stone floor, no window, no door. There were delicate light fixtures on the walls, glowing with a warm, golden light, incongruous with the rest of the room. The sound of a sharp inhale seemed to echo off the walls, and Sam pushed himself upright, searching for its source.

Castiel was bent over Dean in the other corner of the cell. The angel- _ex-angel_- had Dean's face cradled in one hand, slowly rubbing his thumb over Dean's bottom lip.

"Get away from him," Sam said, voice low and angry. The sound of a chain rattling caught his attention as he stood and he frowned at the long line of chain leading from the wall at his back to a collar around his own neck. It wasn't long standing, there was no slack in the chain and he could barely move away from the wall. He rubbed his neck and could barely fit his fingers beneath the heavy band of metal. He settled himself back on the ground in a ready crouch, and the chain fell loose against the wall.

Castiel cast a glance back over his shoulder at Sam, his eyes empty as a scream. He tilted his head slowly, the gesture too-familiar for the monster that had replaced their friend. "Sam," Castiel blinked and turned his attention back toward Dean. "It is fitting that you are awake for this," he said, almost to himself.

Sam caught Dean's eyes over Castiel's shoulder, wide and terrified. Castiel shifted so his hand, pressed low on Dean's stomach, was visible. He pressed down and Dean gasped, back arching off the wall. Dean brought his arms up and swung a punch at Castiel, the motion slow and clumsy. The hit connected but Castiel paid it no attention, eyes flicking between Dean's face and his hand on Dean's stomach.

"What are you doing?" Sam asked, his voice quiet. Something more was going on than he could see. Dean's silence, motions, hell, even his _face_, so openly terrified spelled out clear as day that whatever Castiel was doing, it wasn't good.

"I am cleansing his blood," Castiel said, serene. He leaned in toward Dean and inhaled, his eyes sliding shut and his face falling into an unfamiliar expression of arousal.

Sam blinked in confusion and then the smell hit him. _Bitch_, some part of him sighed out, recognition whispering at the edge of his mind. The distinct smell of an unmated Beta filled the air of the cell, Dean's familiar scent changed, overlaid with the powerful scent of raw potential. Disgust roiled through Sam; Castiel was purging Dean of Androgen-D. He was making Dean ready to _mate_.

"You're sick," Sam whispered, horror stricken. Without the androgen in his system, Dean's body was going to change- had already started changing, from the scent in the air. Sam didn't know how Castiel knew that Dean would develop into a Beta, but his plan was clear. "You can't _force_ a mating!" he yelled, desperate to put a stop to what he knew instinctively was about to become his brother's rape.

"He'll love me." Castiel licked his lips and again scented the air. "He won't be able to help it."

"Fucking- get _off_, Cas!" Dean was too-quiet, coherent speech an obvious effort. "'m not gonna be some _bitch_."

Anger shadowed Castiel's features. "You will be my mate," he said with absolute surety. His grip tightened on Dean's face and a white light shone around the hand on Dean's stomach. "Without the suppressant your body will demand it."

Dean's eyes snapped toward Sam, an expression of deep-rooted terror clear on his face. "I won't," he said. "Cas, you don't get it, I-" he cut off with a gasp and arched off the wall, chest heaving. The room stank of ripe Beta.

Sam's cock twitched. Sam blinked and stared down at his lap. He could see the outline of his cock as it swelled and tented his pants. His attention was dragged back to the other side of the cell as Castiel stood tall and shrugged out of his trench coat.

"Castiel- _Cas_," Sam begged. "Stop this. You know it's wrong."

Castiel ignored him and removed his tie, dropping it carelessly at his feet. His shirt soon joined it, and shirt, shoes and pants followed, until he stood naked in front of Dean. Castiel was hard, cock red and ready between his legs. He stripped Dean with quick, careful hands, totally unconcerned with his nudity, with Sam's pleas or presence at all.

Castiel flipped Dean onto his stomach, the chain connected to the collar at Dean's neck clattering too-loudly in the room. Dean was silent but for his breath, deep gasps that signaled the start of a Beta's heat.

Sam struggled to comprehend what was happening, mind flashing back to an assembly one school had insisted all the kids attend. It hadn't seemed important at the time, a useless lesson on Alphas and Betas in society; Sam was going to be someone important some day, not some moronic knothead or slutty bitch at the mercy of his hormones. He'd been taking Androgen-D since before he knew what it was, a childhood insistence to be just like his big brother meaning he'd been on the hormone-suppressant since he was eight.

Shallow breaths, hormone-stink, raised temperature; Sam couldn't remember all the signs of an oncoming heat, but he knew enough to recognize it when he saw it. He knew enough to know that if Castiel fucked his brother, Dean would be bound to Castiel on a level beyond conscious thought.

The thought of losing his brother- the thought of his brother mind-and-body fucked into loving Castiel- made bile rise in the back of Sam's throat. "He won't be Dean anymore," Sam begged, grasping at straws. "You do this, and what you get won't be Dean. You'll just have some fuck-happy breeder who'll mindlessly follow your every whim."

Castiel settled his hands, sure and easy, on Dean's ass. He spread Dean's asscheeks apart, and the light was strong enough in the room that Sam could see the faint shine of slick. Castiel rubbed the outer rim of Dean's hole, gaze focused on the inflamed rosebud as he spoke. "He will be mine. I will demand his honesty and he will be unable to refuse me." Castiel shifted and Sam's gorge rose in his throat at the sight of Castiel's cock running up the cleft of Dean's ass. Dean arched into the pressure and whimpered, flushed with desperation.

Sam closed his eyes as Castiel leaned in and fucked his cock in, but a tight pressure on his neck had him opening them after a handful of seconds. "You will watch," Castiel said. His voice had lowered with obvious arousal but Sam paid him no attention.

Dean was crying. He was fucking himself back on Castiel, his cock hard and heavy between his legs, but his tears caught the light just as effectively as the slick between his legs. His mouth was slack with pleasure and his tongue flicked out to lick his lips like he was hungry, but that was because of the heat. The tears, the empty look he could see taking root beneath the pleasure- that was all Dean.

"Dean," Sam whispered. He shook himself out of his stupour; his brother was hurting, and Sam wasn't going to let him do it alone. "I'm here, Dean. When this is done, remember that- I'll be here. We'll get through this."

Dean shuddered, at Sam's words or Castiel's thrusts Sam didn't know, and Sam made himself watch. Watch as Castiel grabbed hold of Dean's arms and tipped them backwards so that Dean was perched on Castiel's lap, on full display to Sam's eyes.

He should have felt horrified, and he did. But beneath the horror was a creeping sense of _want_ that Sam didn't understand. Watching Castiel's balls as they slapped up against the flesh of Dean's ass with each upward thrust, the wet sound of Dean's ass as his hole clenched around the cock inside of it, desperate for an Alpha knot. Sam didn't want to see it when it swelled and popped into his brother.

Sam dragged his eyes up and to meet Dean's and let the promise of vengence fill his gaze. Even if Dean got (_his mind balked_) pregnant, even if Dean was mated to Castiel, Sam wouldn't show mercy. If he caught, Dean wouldn't be able to help, but Sam was more than willing to take up the slack in this case. Some part of him (maybe all of him) just wanted to make castiel _pay_. The wet trail of tears down Dean's cheeks continued unchecked had Sam choking on rage and his own tears.

Castiel encouraged Dean to fuck himself on his cock and Dean's instincts forced him to obey. Dean was splayed over Castiel's lap, his bare knees pressed hard into the rough ground, red and pockmarked by small stones that his weight had dug into his flesh. Sam could see the dark smudge of bruises on Dean's hips, the faint shadow of Castiel's hands infuriating against the pale of Dean's skin. Dean nipples were dark and tight on his chest, his cock dark against his belly, but his movements were slowing, the desperate, heat-induced edge from a few moments earlier fading into a helpless twist of his hips, as though desperately searching for... something.

Sam's eyes reluctantly trailed down to Dean's hole, red and swollen with heat, and studied Castiel's cock. Castiel was still thrusting, the tireless stamina of an angel meaning every flex of his hips was hard, fast and perfectly timed with Dean's movements. Sam could see the entire length of Castiel's cock every time he withdrew and it struck him, suddenly, that Castiel didn't have a knot. A short bark of laughter broke out from Sam and he met Dean's stricken gaze with his own. "He's not an Alpha," Sam said, relief colouring his voice with black humour. "He's dead-set on mating with you and he _doesn't even have a knot to do it with_."

Castiel slammed Dean down hard on his cock and Dean's hole fluttered wildly around the base of the cock inside him and couldn't help but notice the slow ooze of juice from Dean's hole leaking unimpeded down Castiel's shaft. There was no knot to stop it, which meant no pheromones that would kick-start a Beta into full estrous. No mating cycle to fuck with Dean's head or heart to confuse his loyalties.

"You're fucked," Sam said with surety. "His body is just," his mind desperately put together pieces of a puzzle he knew too little about, "reacting to the change. This isn't a heat. This is just _puberty_."

"You're wrong," Castiel growled. His eyes were dark, barely visible over Dean's shoulder. "_I_ triggered this heat, not an Alpha. His body will react accordingly." Castiel's hand splayed out over the pale skin of Dean's abdomen. "There is no other option; he will accept me." His motions were frantic, angry; he didn't fuck Dean like a man sure of the outcome and it slowly dawned on Sam why.

Dean hadn't come yet. He was a Beta being fucked in what Sam could believe was the grips of a genuine, if falsely induced, heat- everything he'd heard whispered about the wild fucking that was inevitable when people stopped taking their suppressants said that Dean should have been a mess, fucked out and covered in his own come as he was bred. But he wasn't. Dean was _wet_, covered in sweat, tears and the slick from his ass, but there wasn't even a sign of precome on the tip of his cock.

"It's not working," Sam said and Castiel's snarl of rage confirmed it. "Dean's going to come out of this soon. He's going to wake up and he is going to _hate_ you." Sam wanted the words to be true. Was desperate for them to be true. But Dean and Castiel- they had been close, and it took a lot for Dean to burn a bridge, and people hurting him, playing him, wasn't always enough. He'd forgiven Sam, after all.

Sam had more than enough hate for both of them.

Castiel slid his hands under Dean's thighs and lifted him, inhuman strength making the move look easy. Dean grunted in protest as Castiel's cock slid from him in a wet sounding slide. Sam caught a brief glimpse of the inflamed hole winking open and closed before Castiel gently settled Dean onto his back. Dean lifted his hands to Castiel's grip at Castiel's shoulders, the first sign of deliberate movement Sam had seen from him in what felt like far too long. He stared up at Castiel, that same empty look on his face, and Castiel softened under his gaze. Castiel leaned in close, Dean's name a quiet whisper of breath, and Dean spat in his face.

Castiel blinked and the affection bled out of his face, replaced with a cold, hollow desperation. He rolled his hips forward and slid inside Dean again, but his motions had lost any hint of softness he'd had in the previous coupling. He fucked Dean with a brutality that bellied his lack of knot. He tore Dean's hands from his body and pinned them above Dean's head with one hand and slotted his other to Dean's shoulder, where the scar of his mark was just visible.

Dean twitched at the touch but just started to struggle harder, and Castiel growled in frustration. His motions were desperate, but ultimately useless. No knot swelled. No mating-bond was created. Dean's cock had even started to soften, and Sam felt a surge of victory. Betas always wanted their mate- were always receptive to potential mates. Castiel was neither.

That didn't stop him from fucking Dean. Castiel released Dean's hands and gripped Dean's dick in his hand as he fucked him, but Dean just softened further, his body withdrawing from Castiel in the only option available to it. It went on for too long, Castiel's desperation showing through in his obvious, slightly clumsy attempt to target Dean's prostate. Eventually he came, held tight inside Dean's body. Sam might have heard a sob when he did, but when Castiel pulled out his face was calm, collected. His cock gleamed wetly in the light, and Dean's ass was a fucked out mess of juice and slowly leaking come.

Sam strained forward, the pull of his collar against his throat unimportant when held against Dean's stillness, Dean's- hurt. "Let me see him," he said. "Please, Cas, just. I won't do anything, just let me see him."

Castiel stared at Sam, spine straight, and made no move to cover himself. The edge of his foot was touching Dean's calf, and somehow that one point of contact, so careless, brought a wash of tears to Sam's eyes. "Please," Sam begged, pride nothing next to the need to touch Dean, to offer whatever comfort he could.

In less time than it took to blink an eye, Castiel was gone and Sam on the opposite side of the room, his collar bolted into the wall next to Dean's. Dean jerked upright and stared at Sam, his eyes too wide and his skin pale enough to make his freckles stand out in sharp relief. _No stubble_, Sam realized, and shuddered as the first hint of how this would change their lives after they got out (because they _would_ get out of this) chased around the edges of his thoughts.

"You okay?" Sam asked. He stripped his shirt off and draped it over Dean's shoulders, then couldn't stop his hand from creeping forward to touch the tips of his fingers to Dean's, desperate for contact, for the affirmation that Dean was still here, still alive, still- not broken.

Dean snapped his eyes down to Sam's hand on his own and a full shudder worked through his body. His cock, flaccid against his thigh, twitched and swelled with blood. Sam froze as the smell of Beta-heat rose again in the air, so thick he could hardly breath, let alone think. His own cock was hard- had never softened, he realized. Confusion washed over him and he moved his grip up to Dean's wrist, anchoring himself. "What's happening?" he asked, and his voice was low with building arousal.

Dean's pupils were huge, only a bright ring of green visible around their rim. His voice, when he spoke, was steady, and Sam calmed at the sound of it before his words filtered in. "The Terminator version of you," he licked his lips and Sam couldn't help but follow the motion with his eyes, "He wasn't exactly- responsible. By the time he met up with me he'd stopped taking Androgen at all." Dean laughed and glanced up at Sam from beneath his lashes. "He put even me to shame, practically banged anyone that bothered to stay still for long enough."

Sam's stomach twisted in on itself. "Did he. Am I _mated_ to someone?" Sam whispered, horrified at the thought he'd been mated to some random hookup he couldn't even remember.

Dean shook his head. "Not that I could tell." Relief crashed through Sam. Relief that he didn't have to deal with that and, again, relief that Castiel hadn't been able to do that to Dean.

Sam blinked, and looked down at their joined hands. "That's why Castiel couldn't mate you," he said slowly.

Dean nodded, the motion jerky, stilted. "A Beta won't mate with anyone but an Alpha if the option's available," he agreed. His lips quirked upward, a sad shadow of a smile. "You always do have my back."

Sam gave in to what his instincts were screaming at him to do, and gathered Dean into a hug. He ducked his head down into Dean's neck and ignored the way his cock twitched at the strong smell there. "We'll get through this." They had to.

Dean nuzzled into Sam's neck and the tension bled out of him. "You and me against the world, huh Sammy?" he whispered, and the rough edge of tears cracked briefly through the facade of normalcy Dean was always so desperate to maintain.

Sam squeezed his brother close. His cock was still hard. So was Dean's.


	2. Chapter 2

Additional warnings for this chapter: fisting

The sun creeping into his eyes woke Dean; he squeezed his eyes shut against it and rolled over in an attempt to avoid the bright light. He turned over and breathed deeply for a few moments, reveling in the scent of his mate, heady and strong. Dean blinked the sleep-gunk out of his eyes and cringed as his lashes tore and squinted at Castiel. He couldn't stop the smile that bloomed over his face. "Hey," Dean said.

Castiel smiled at him, relief painted over his features. He reached out and touched a hand to Dean's cheek. "Good morning."

Dean stretched until his arms hit the top of the headboard, then spread them out so his fingers brushed the handcuffs left there from the night before. His wrists twinged at the memory, a pleasant throb that would stay with him the rest of the day. Dean let his hands fall down and tangled his fingers into Castiel's hair, drawing him forward. "You wanna start the day off right?" he asked, lips brushing against Castiel's.

Castiel's eyes brightened and a dark, predatory look spread across his face. He kissed Dean, his mouth relaxed and easy against Dean's, feeling out the shape of Dean's lips. Dean opened to the pressure and licked at Castiel's lips; they were perpetually chapped and felt rough against his tongue. Castiel rarely bothered to eat or drink, and his body seemed to be in a state of perpetual dehydration because of it. Dean rolled Castiel's taste over his tongue to fill his mouth with spit and let the kiss turn wet, sloppy.

Castiel drew back from the kiss and lay back. He grabbed hold of Dean's hand and tugged, positioning Dean until he was perched atop Castiel's thighs. Dean reached down and lifted Castiel's testicles out of the dip of his legs and squeezed his own thighs in, so Castiel's were pressed together and his balls could rest atop them. He edged forward until his own balls touched Castiel's, hot and rough. He hummed in pleasure and the contact and reached down for his cock; he smiled at Castiel as the angel slid his hands up from Dean's knees to his hips, then slid them back to grasp the cheeks of Dean's ass. Castiel smiled up at Dean and trailed his fingers down the crease of Dean's ass, a light touch against the sensitive skin. He lingered over the slick dip of Dean's hole, one finger dedicated solely to dabbing into Dean's hole on each stroke.

"You're in estrus," Castiel said, voice absolutely casual. A shudder ran down Dean's spine and his hole clenched down tight as Castiel pushed in finger in deep. "Should we use a condom?"

"Fuck, no," Dean said. His hole was begging to be filled, all his instincts demanding to be bred. The thought of sliding a condom over Castiel's cock, of putting a barrier up between them when they'd never bothered with it before, twisted his insides up with knots of anxiety. Castiel was his _mate_, and mates had no barriers between them, just like S-

Dean tipped forward and canted his hips up, and his knees spread wider on the bed, so he was open to Castiel's touch and their cocks were pressed together between their bellies. His nipples, swollen and sensitive, peaked as they slid over the slick skin of Castiel's chest and he rolled his hips down. Castiel rewarded him by pushing two fingers into his ass and curled them into a hook, pulling back against the tight muscle of his rim. Dean moaned and propped himself up on his elbows, back a tight arch to keep him pressed in contact with Castiel all down the line of their torsos.

"You want your body to swell with my seed?" Castiel asked. Dean jerked, but Castiel's fingers in his ass, curled up inside him, kept him in place. Every part of Castiel was preternaturally strong, including his fingers. He didn't need a firm grip on Dean to keep him in place, Castiel was _just that strong_.

If Castiel didn't get with the program and fuck Dean _no_, there was going to be Hell to pay. "I wanna be so full of come it leaks out of me when I walk," Dean rasped. He shifted forward and dragged himself up Castiel's body with his arms, so his cock dragged up Castiel's as he went. The wet trail of Dean's precome painted Castiel's cock and stomach, clear and watery. He could feel his own wetness decorating his skin down to his thighs, and it filled the room with his own smell, so much more potent than the fluid from his cock. He could still smell Castiel beneath it all (familiar, _home_, Alpha) though his scent was mixed with an out-of-place hint of _child_. It was disconcerti-

Castiel withdrew his fingers from Dean's ass and slid it down under Dean's pelvis and _lifted_ him, taking all of Dean's weight without batting an eye. Castiel's other hand snuck down, beneath Dean, and tipped his cock upward, until the head brushed against Dean's pucker. Dean's hole was wet, loose and ready to be filled. He pushed himself down against Castiel's hold on him and swore softly when Castiel's cock stayed stubbornly out of reach. Castiel rubbed his head in a circle around Dean's rim, and the muscles of Dean's ass relaxed at the touch; his insides pulsed, and another trickle of slick poured out from his hole, wetting Castiel's cock and blending their scents.

Castiel slowly lowered Dean down, until his cock caught on the soft, wet center of him, and the head slipped in. He kept Dean perched there on the tip of his cock, unable to grind down and unwilling to lift off. "Cas, come on, _please_," Dean whined. The pressure of Castiel's cock in his ass had his temperature sky rocketting, all his instincts screaming at him to finish the coupling, to get _fucked_, to do all he could to plant Castiel's seed inside himself.

"Would you rather I use you for my pleasure?" Castiel asked. He gripped Dean with both hands and lowered him on his cock. Dean shuddered at the pressure inside him, shallow enough that the penetration just made him want more. Castiel jerked his arms so Dean slammed down one precious inch more, enough that Castiel's cock stabbed into his prostate, but froze again once Dean was there. Dean cried out and squirmed in place, desperate for more of that contact. "Or would you rather ride me, like the come-hungry slut you are?" He abruptly released his hold on Dean, and in that moment of surprise, gravity had Dean falling down all the way to the base of Castiel's cock.

"Oh my _god_," Dean gasped out. He let his head fall back, brought his hands up and tangled his hands into his hair, pulling it roughly to distract him from the intense pleasure of finally, _finally_ being filled. The swell of Castiel's knot hadn't locked them together yet- hadn't started to fill at all, by the greedy feel of his ass- and Dean took the opportunity to lift himself up and drop down again, the full slide of Castiel made easy by his wetness. "You gonna tie with me?" Dean could barely recognize his own voice, so low and breathy.

Castiel let Dean grind down on him and trailed his hands up over Dean's chest, casually possessive. He curled one hand around Dean's ribs and thumbed harshly at Dean's nipple, and lightly traced the outline of his hand print on Dean's shoulder. "I will," he said. He moved his gaze from Dean's chest and stared him full in the face. "Eventually. Do you think you can convince me to hurry up?"

"I'd love to," Dean breathed, and deliberately clenched the muscles in his ass. He _watched_ as Castiel's eyes dilated at the pleasure and his whole body lit up with the pleasure. He spread his knees out on the bed so he sunk that extra half-inch down onto Castiel's cock and straightened, so the light of the sun shone bright on his sweat slick skin. Castiel's gaze was greedy, a palpable weight on his skin. He slid his hands down his abs and rubbed his fingers into his pubic hair, teasing himself, before he slid his hand around his cock in a loose hold. He wouldn't be able to come until he was knotted, not with the way his body was begging to be bred, but that didn't mean he couldn't put on a show.

He masturbated slowly, familiar with his body, confident in his ability to tease himself without bringing himself to the point of agony. Castiel watched him hungrily and stroked his hands all over Dean, shoulders to elbows, down his back to his ass, over his thighs. Eventually Castiel settled his attention on Dean's ass; he rubbed one finger up the sensitive line of Dean's crack, playing with the slick.

"Yeah, that's good," Dean purred. He added a twist to his strokes, and tilted his thumb in so it would catch on the flared edge of his crown on every stroke, a sharp point of pleasure that could have so easily slide into pain if his body wasn't so filled up by his heat. When Castiel slid his finger down and pushed it in alongside his cock he froze and then pumped himself harder. He used his other hand to dab at the slit of his cock, then brought his precome coated finger up to his mouth. He licked his finger and hummed in pleasure at the taste, and then slid two fingers deep into his mouth. He didn't need to worry about technique- they were his fingers, after all- but he sucked and tongued at them anyway. It was a raunchy, sluttish impulse, but Dean couldn't help but love the feeling of sucking something when his ass was so fantastically full.

"You want my knot?" Castiel asked. He fucked his fingers up into Dean alongside his cock, used them to find and press on Dean's prostate. "You want me to father the next generation of Winchesters? Want to be bred until your lines of _family_ so thoroughly you look to me first?"

Dean furrowed his brows and looked down at Castiel, mouth still full of his own fingers. He slid them out with a wet pop. "Cas, what are you-" and was cut off when Castiel abruptly jerked his fingers out of Dean's ass and flipped them over, still buried inside Dean. The sun in the room seemed to fade away, replaced by the darkness that spread over Castiel's face.

"You're _mine_," Castiel growled. He kept fucking into Dean, and the scent that had bothered Dean before, the smell of immaturity, infertility, _non-Alpha_, suddenly poured from every pore in his skin, tainted the smell of his sweat. Dean squirmed underneath Castiel's weight, terrified, and woke up with his face pressed into Sam's crotch, cheek just touching his knot.

He blinked. The musk from Sam fogged his thoughts, and line between _there_ and _here_ blurred in his mind. He wondered where Castiel was, how he'd ended up here with his brother, and then reality crashed back into him with the force of a poltergeist. Dean scrambled up, away from his brother, from the smell that made his gut clench tight in anticipation.

The loss of Dean's weight against his legs woke Sam; he stared blankly at Dean for a long moment, t-shirt clinging to the contours of his chest, his cock- his _knot_- bulging obscenely against the line of his pants. Dean's mouth watered just thinking about it and he curled in on himself, back pressed hard against the cold wall. He tucked his foot in close to his groin, so the slick (his own or Castiel's?) leaking from his ass wouldn't be visible. Dean could smell it, though. Feel it, leaking from him, leaving him so fucking _empty_ where he was meant to be full.

The most terrifying thing about his thoughts were how natural they felt. It wasn't like the itch he got between his shoulders sometimes, when he went looking for broad, hard bodies instead of the soft warmth of a woman. It was a hunger, and it made his body _ache_ with it, a constant distraction that thrummed beneath the surface of his thoughts.

Dean blinked the spots out of his vision. His chest felt tight. He hunched himself inward, ignoring the ache in his ass Castiel had left behind, ignoring how it just made him want _more_, not thinking about that dream, that fucking _dream_ where he'd felt so happy, nothing more than a puppet dancing at Castiel's whim, body mated and mind washed away. He didn't want that. He didn't. His body was begging for it, but _he_ didn't want it.

"Dean!"

Sam's voice broke in on his thoughts and Dean snapped back to himself, Sam's anxiety a beacon he never could ignore. He brought his arms down from his head (he didn't remember bringing them up, couldn't tell how long Sam had been calling him, a gross lapse in the vigilance he had to keep up, to keep Sammy safe), forced his uncooperative limbs to uncurl. Sam, pale-faced and desperate, was crouched just out of reach. Good. Smart. Dean wasn't sure that he would have been able to resist taking a swing, with how raw his nerves felt.

Sam made an aborted motion to reach toward Dean and Dean couldn't stop himself from flinching backwards, all his instincts screaming at him to lean into the touch. Sam froze in place and then settled himself back down against the wall, facing Dean. "What just happened?" he asked, voice hoarse; his throat was bruised around the line of collar, dark and obvious, bad enough to affect his voice box.

Dean broke the heavy eye contact Sam. He drew Sam's shirt closed around himself, desperate for any shred of comfort, protection. "Nothing happened. I was dreaming." He kept his head raised by force of will alone, eyes locked with Sam's wHen all he wanted to do was duck down, hide away.

_Bullshit_, said Sam's face, but he let it go. "You got any bright ideas?" he asked, turning his attention to their cell. Dean grasped at the distraction gratefully. The room was almost entirely bare; there were the lights, too high up to be torn from the wall, but that was it. No windows, no door- there wasn't even a toilet, Dean's bladder was annoyed to see.

"We could try the angel banishing sigil," Dean said. With the attention off his _well-being_, he let himself edge along the wall, toward the heat pouring off Sam's skin.

"There's no way to know that would work."

No, there wasn't. The Angel Sword hadn't even phased Castiel, and the sigil wasn't nearly as powerful. "Even if it did, getting rid of Cas wouldn't give us a way out of here." The cell felt smaller all of a sudden, like the walls were breathing in, expanding toward them. Dean shook off the feeling; now was _not_ the time for that bullshit. Dean turned his attention back toward Sam; looking at his brother always made the walls seem further away. "One of us would need to bleed to draw it and then we'd still be trapped. We'll have to wait and see."

"You should not concern yourself with such petty matters," Castiel said, suddenly there in the middle of the room. "I would not allow either of you to come to harm."

Rage washed over Sam's features. "You think you didn't hurt Dean last night?" he asked, incredulous.

Castiel's face was calm, like the surface of deep, cold lake. "I am only doing what is necessary." He strode toward them, hand outreached, and before Dean could even think to protest, Castiel's palm was pressed to his- to Sam's, Castiel shouldn't fucking _touch_ him- forehead. A jolt of electricity went through his body and then Castiel was back, out of reach, and Dean. Dean wasn't hungry anymore, didn't have to piss. His ass felt like his ass again, not a bruised, wanton mess. But he was still wet inside, still hungry.

"What was that?" Sam demanded, voice sharp.

Castiel blinked at them, languid. "Your bodies required tending," he said, like that was any fucking explanation at all.

A laugh spread through the corners of the room, and Dean was startled to realize it was coming from him. "A God's got to take care of his _subjects_, huh?"

"I have always taken care of your needs," Castiel said. It was sick, listening to Cas talk like this. Sick and heartbreaking, because Dean could almost see, could almost _believe_, that his friend was still beating around inside the monster before him.

"What we _need_ is for you to let us go," Sam said. He'd moved into a crouch, tightly coiled as a spring. If Castiel came within reach of their chains again, Sam would be ready to dish out- nothing. They wouldn't be able to put a mark on Castiel, hadn't been able to hurt him ever before he took a heavy dose of Monster-steroids.

"You've already failed to fuck me onto your side," Dean said, and relaxed when Castiel turned his attention back to him, away from Sam. "What's next; you gonna body-hop until you find a meat suit that my heat recognizes?

The temperature in the room suddenly dropped and Dean shivered. Castiel's expression didn't change at all, but the air was suddenly filled with a static charge, just waiting for a spark to ignite.

"Your body will recognize this form," Castiel said. His voice hadn't changed, but the room shuddered  
>with its vibrations.<p>

Sam narrowed his eyes. "Wouldn't it be easier to just use a vessel that has a knot?" he said, and Dean gave him a dark look, because giving Castiel _ideas_ was just not fucking on.

The tension in the room was suddenly gone, tucked back inside Castiel's bland expression. "I am no longer an Angel, Sam. This body is mine, has always been mine. No other form could host a god." His eyes went distant. "I can feel the paths my Father used to create it, and I cannot yet change His blueprint." He focused in on Dean. "But I changed your form. I have remade you now threefold. It is mine, just as I was once my Father's."

A shiver ran through Dean, goosebumps spreading out from his center. His shoulder throbbed.

"What happened to Team Free Will, Cas?" Dean pushed himself to his feet, backed up against the wall so the chain wouldn't cut off his breath. "You given up on that?"

"Children require guidance if they are to make the right choices." Castiel's face didn't change, but Dean could suddenly taste the bitter tang of regret on his tongue. He flicked his eyes toward Sam, who looked the same as ever- not a good sign. If Sam wasn't feeling this shit from Cas, that meant- Hell, Dean didn't know what it meant.

In the blink of an eye, Castiel was in front of Dean. He cupped Dean's smooth face in one hand, his palm warm and dry against Dean's skin. Dean froze. Castiel's eyes were bright blue, and he couldn't help but think of his dream, how _happy_ he'd felt, how much he'd loved Cas, even if it had been a lie. Castiel brushed his thumb over Dean's bottom lip, gently. "I will show you the way," he said, and leaned forward and kissed Dean.

Sam was suddenly there, pushing Castiel back. His face was flushed red, his teeth gleaming sharp in his snarl. "Don't fucking touch him." Castiel didn't move; he may as well have been anchored in place, for all the good Sam's efforts did.

"You are to be our witness, Sam," Castiel said. There was no sign of effort, no sign his attention wavered from Dean for even a moment, but between one breath and the next the links of Sam's chain were sucked back into the wall, dragging him back, until the the back of the collar was flush with the wall. Sam's head was forced forward by the position, his chin tucked in close to his chest.

Dean shoved forward in an effort to get to his brother, but Sam reached out one of his mammoth arms and slapped the wall next to Dean hard enough that Dean could feel the vibration. "Is this some kind of sick marriage to you?" Sam asked, the pain of such sudden restraint obvious. "You think I'm going to give you my _blessing_?"

"Your opinion is not important. You do not _need_ to be here, Sam," Castiel said as he slid his hand under edge of Sam's shirt and felt out the edges and contours of Dean's shoulders. "I merely think it would be proper. If you would rather not bear witness to our union, you must only say so. I will let you go. Otherwise, _be silent_."

Dean watched the thoughts play out over Sam's face, obvious as anything. Any other situation- any other time- Sam would want to take the offer, regroup and to help find a way out of this place, find a way to get Dean out. But Sam couldn't leave. Not if he wanted to find Dean intact once he was rescued; not if he wanted Dean to keep his soul. Without Sam there, without an Alpha keeping Dean's mating instincts along the rigid lines of Alpha preference, Castiel would get what he wanted. He would get Dean's soul.

"You should go, Sammy," Dean said. His throat closed up, his eyes stung. "Get out of here. You don't, you don't need to see this."

Sam stared at Dean in disbelief and then conviction fell over his features like a cloak. "I'm not leaving you," he said, like _Dean_ was the idiot.

Castiel leaned forward and nuzzled Dean's neck, affectionate and mercurial as a cat. "You see, Dean? Your brother approve of our union." There was a strangled sound from Sam, who seemed unable to form words. "He'll be our silent observer." Castiel pressed a wet string of kisses below Dean's ear, down his jawline, over his chin and ended at his lips. "I thought of a way to ensure your body's cooperation."

Dean was spun around and his arms were forced up against the wall next to the bolt of the chain. He couldn't pull his wrists free- couldn't move them at all. Dean shuddered at the feel of Castiel's hands on his hips, gently pulling him back and up, putting his ass on display. For a too-long moment, his mind flashed back to the dream, to the feeling of wanting this, but then smells in the room hit him all over again. Castiel didn't smell like an Alpha. He didn't even smell fully human, a strange undertone of ozone dogging the edges of his scent.

Castiel spread his hand out over Dean's lower back and sent a pulse of power through Dean. The urgency of heat crashed over Dean all over, amped up to full. He felt _hollow_, liked he'd be scraped out, so much worse than the persistent hunger of before. He moaned, long and low, and turned a desperate stare on Sam, so needed but out of reach in so, so many ways.

"We're going to try again," Castiel said. Dean could hear the slight rustling as he dropped to his knees behind Dean. He pressed his knees against the inside of Dean's legs to widen Dean's stance, and Dean shivered at the cool feeling of air against the wet skin of his entrance. The smell of his own musk filled the air, his body instinctively trying to attract the Alpha it was so desperate for.

Castiel pressed one finger, then two, into Dean. It was easy to take them and his ass clenched instinctively around the penetration, a shadow of how he'd milk a knot. Dean shivered at the feeling; his nerves were more sensitive than they'd ever been, the stretch against his rim better even than a touch to his prostate. Castiel scissored his fingers and added a third, the pressure against his insides delicious but never, never enough. Castiel ran his other hand down Dean's back as he pumped his fingers in and out, one hand slick with Dean's sweat, the other with his body's natural lubrication. Castiel wasn't bothering to aim for Dean's prostate, his attention focused on spreading Dean open on his fingers, his fingers firm and unforgiving against the softness of Dean's insides.

"Just get it over with," Dean grit out between clenched teeth when Castiel just kept playing with his hole, just kept rubbing circles into the soft, greedy center of him. He was hard and heavy between his thighs, every touch against his skin electrified.

"Patience," Castiel said, voice hoarse. Fingering Dean obviously did it for him, and bitterness welled up inside of Dean. He missed Castiel all of a sudden, an ache entirely separate from the hunger of his heat. He missed his friend. He missed Cas, but he couldn't help but wonder if this version of Cas had been lurking beneath the surface the entire time, just waiting for the right moment to emerge. Dean didn't want to believe it. He didn't want to doubt it.

Dean whined as Castiel slid in a fourth finger and pushed inside past the line of his knuckles, up to the joint of his thumb and rotated it. Dean dropped forward so his forearms were pressed to the wall, his elbows dug in hard. He dropped his head down between them. His hole felt stretched wide, but only in on direction, and it wasn't enough, still wasn't _right_, and that just made him want it more. "What are you doing?" Dean gasped out. Cas rubbed his fingers roughly against Dean's prostate, a hard push against his insides like he was scooping out a handful of mud, trying to press past Dean's ass to the soft flesh of his insides. Pleasure washed over him in a wave; he panted, voice too loud in the otherwise silent room. He couldn't look at Sam, couldn't see Sam's face as he turned into such a fucking slut at his own rape.

"Your body needs the stretch of a knot," Castiel said. He slid his hand out until just the tips of his fingers were inside, and Dean cringed at how empty he felt without the stretch. "I am going to give your body what it needs." When he pushed his fingers back in, his thumb was tucked in tight against his palm.

Dean's eyes shot open, and jerked against the restraints, trying to escape the absolute _wrongness_ of being stretched in this way. "Stop," he said, quiet, then louder, "Cas, stop it!" He tucked his hips in forward as far as he could but Castiel just followed him, pressed inside. There was a brief, painful moment were Dean didn't think Castiel would be able to get his hand inside, that he'd have to _stop_, and then Castiel's hand sunk in to the hilt. It wasn't a knot, and all of Dean's instincts screamed at him to expel the intrusion, but he couldn't. He just had to fucking kneel there and take it. He whimpered and jerked his hips forward and back, trying desperately to find a comfortable position. His rim clung tight to the skin of Castiel's wrist, and the stretch burned.

"You're so wet inside, Dean," Castiel said, voice reverent. He curled his fingers into a fist just on the inside of Dean's hole, and it was so wrong, but it was almost like a knot. It was a different kind of pressure against his prostate, and it was almost enough. Dean sobbed out and his cock leaked a spurt of precome onto the floor. He might be able to come from this. He might be able to come from Castiel's fist in his ass, and if he did, he'd be mated. He'd be worse than dead. Castiel straightened his fingers and felt along the walls of Dean's hole, pressing gently first forward and then back. The base of his palm pressed into Dean's prostate while his fingers explored, and the feeling of it made his breath catch in his throat. And then Castiel's fingers pressed on something- further back. Dean gave a full body twitched and then could stop himself from tilting into the touch, desperate for more.

"What is that?" That couldn't be Dean. Not with that low, fucked out, slutty voice.

Castiel made a low sound of satisfaction. "That is the Beta male version of a cervix Dean." He rubbed along the spot with his fingers, soft, just touching it. It felt almost like a cut, the same kind of open wound Alistair would cut into him to fuck sometimes, but unlike what happened in Hell, Dean didn't have pain to fight through to find the pleasure. Castiel's touch sent fireworks off inside of him, intense bolts of pleasure that made him want to beg for more. "It's meant to be inaccessible without a knot." His voice was filled with smug satisfaction, and a cold drop of sour sweat dripped down Dean's face, terrified at what this meant. "All it needs it a planted seed."

With that, Castiel withdrew his fingers from the toohot spot inside Dean, and stretched his fingers wide. Castiel was strong enough that Dean's ass opened, his insides touching _nothing_ where he was spread around Castiel's fingers. Castiel pulled his hand out in a slow glide, his fingers opened wide inside of Dean's ass. He tried to clamp down against the too-hard pressure, but Castiel's fingers stayed as they were, painful and somehow hotter than anything Dean had ever imagined.

A strangled sound of protest came from Sam's direction and Dean looked over at his brother, who was staring at him (shouldn't look, Sam shouldn't have to see Dean like this). Sam's lips were moving with soundless words, and Dean blinked and then understood what Sam could see that he couldn't.

Castiel had withdrawn his hand until only his fingers were still inside Dean, and he kept them spread open so far the pink of Dean's insides felt on display, exposed by Castiel's will. The air felt cold on the inside of his hole, unused to the feeling of air at all, but it was gone before it could become uncomfortable, replaced by the hot, blunt pressure of Castiel's cock against the vulnerable skin of his insides.

"Cas?" Dean asked, voice tight. There was no answer except for a sudden blunt pressure against the exposed flesh of Dean's hole. Castiel's cock sank into him easily, a slow slide that had Dean clenching his teeth and fighting back a second wave of tears. Castiel slid into Dean between his fingers, but it was still infinitely easier than taking Castiel's fist had been, a deep, slick slide inside.

"You see?" Castiel rolled his hips forward and Dean choked back a cry, surprised Castiel hadn't bottomed out yet. He felt tender inside, and Castiel's cock working inside felt like Castiel was fucking into a bruise.  
>The peaks of Castiel's knuckles pressed into Dean in a sharp chain of pain, linked by the softer throb between. His nail caught against the thin skin of Dean's rectum, but slid off without catching, the path smoothed by the slick juice. Every time Castiel adjusted his grip it felt like an animal writing inside him. "Your body craves this."<p>

"You're sick," Dean whispered into the crease of his elbow, but Castiel was more right than he knew. Dean's cock was still hard, and his ass was still producing natural lube, slick and welcoming as a girl's pussy. His body wanted this, welcomed it, a deep primal need that would destroy him unless he could pull through.

One of Castiel's hands slid around Dean's chest and pressed flat against his sternum and then drifted lower, over the soft flesh of his underbelly, and the fingers of the other slid deeper into Dean's ass, just like in the dream.

This was nothing like the dream.

There was no escape from the reality of Castiel's betrayal; there was no underlying connection, no _relationship_, to make this something Dean would want. He had no connection with the being fucking him, no friendship. That had died back in that warehouse with Raphael. If Castiel mated with him after this, it would be a mockery of the friendship they'd had before.

Dean focused his attention on the wall in front of him and strained for the sound of Sam's breath, then matched his own to it. He didn't need to remember this, and Castiel didn't deserve Dean's attention. He forced himself into the meditation patterns his Dad had taught him as a kid, found the calm that he'd needed to first shoot a gun with a steady hand. His body relaxed and even the painful force of Castiel inside him faded away. The stone was grey, shot through with the occasional fleck of pink. It was pretty.

He felt it when Castiel's hand slid back into his ass, obviously gripped around Castiel's cock in a poor man's imitation of a knot. His body responded to the feel; the urgency of his heat tried to break over him but Dean just thought about the cold air of morning out at Bobby's, about Sam's smile when he thought Dean wasn't looking. Really, what Castiel was doing didn't matter at all.

"None of that, Dean," Castiel whispered into Dean's ear. The hand pressed against Dean's front tensed, and then pushed _in_, and-

And-

Dean screamed, fully present inside his own skin again. He was stretched too thin, his ass throbbed violently in time with his heartbeat, and Castiel's hand was moving inside him around Castiel's cock, Castiel was masturbating _inside Dean_, but that wasn't nearly as bad as the feeling as Castiel grabbed hold of Dean's soul and _twisted_.

"Stop it!" Sam yelled, released from his silence by Castiel's distraction. "Cas, you're hurting him, _let him go_!"

"I can't." Castiel's voice seemed to come from a long way off but it shook the foundation of Dean's bones, a too-strong wave of _Castiel_ moving through his soul. "I must complete the mating."

The hand wrapped inside Dean flexed, pumped up like a knot, and Castiel began to thrust in ernest. His fingers were pressed against Dean's prostate, and at the deepest point of penetration Castiel brushed up against that other place, that place Dean wished with everything he had didn't exist. Pleasure shocked through Dean, but it was agonizing, soul-deep terror suffused with a possessive intent Dean recognized as Castiel's, doing its best to meld their pieces together.

Castiel fucked Dean hard, fucked him long enough that Dean's thighs were drenched with liquid that had leaked out from our the dual blockade of Castiel's fist and cock. He fucked and fucked and_fucked_, and for every moment of it Dean was held on the edge of orgasm, unable to tip over.

Eventually Castiel came, his come just a drop in the ocean of the mess that was Dean's ass. He slid his cock out first, and then his hand, and Dean shuddered at the squishing sounds his hole made at the loss. Castiel loosened his grip on Dean's soul and stepped back, out of Dean.

Dean couldn't move, still held in place against the wall, but his thighs were quivering with exhaustion. "This isn't going to work, Cas," Dean said, head hung low between his shoulders. "Just let us go."

Dean didn't need to be able to see Castiel's face to see the rage and fear that would be there. "No," Castiel said.

And then he was gone.


	3. Chapter 3

Their chains disappeared with Castiel, and Sam was up and on the other side of the room before the freedom had fully registered. He eased Dean's hands down from the wall, and gathered him in close, half in Sam's lap, and turned his back on the room so Dean was pinned between his chest and the wall. It wasn't much, but it was the most protection Sam could offer. Dean didn't struggle, just wrapped his hands around Sam's biceps and clung there, curled in under Sam's chin. The intensity of the musk on the air made every breath an act of torture, and the press of Dean's skin to his own just made it worse, sickening desire shooting sparks through his body.

"We'll make it through this," Sam promised, and he stroked a tentative hand down the line of Dean's spine, the skin clammy and cool. They were both shaking, but as they clung together, it calmed. Dean's skin warmed at his touch, and eventually he tensed in Sam's arms, but didn't pull away.

"This can't last, Sam," Dean said, dully. "Sooner or later, Cas is going to figure it out." He paused, and straightened, drawing back so he could look Sam in the eye. "If he mates with me, I want you to kill me," he said with the utter conviction of the doomed.

"Dean-" Sam managed, and couldn't make himself say more.

Dean stroked his fingers over Sam's cheeks to his hair. "I'd rather be dead than his." His voice was so- matter of fact. Like he wasn't asking Sam to rip out half of his own soul.

Sam swallowed and tipped his head down so their foreheads brushed. "I won't let it come to that," he said, a vow he'd lay down his life for.

Dean laughed, hollow. "Sure, Sammy." He closed his eyes briefly, and when they opened again the steele core of strength that Sam knew so well was right there on the surface, unflinching. "But you need to promise me you won't leave me like that, with him."

_Never_, agreed some dark, twisted corner of Sam's mind. He didn't know if the thought came from the cold, efficient killer of his rogue year and a half or from the angry, possessive Alpha side of him that would rather bathe in a sea of red than have its bitch belong to someone else, but Sam didn't care. It wasn't going to be a issue.

Dean needed more than platitudes, though. Sam sucked in a deep breath through his nose. "I won't let you be his," he said. Dean took that at face value, and for that Sam was glad. The thoughts that were beginning to take shape in the back of his mind scared him, and Dean had enough on his plate as it was.

A plan began to take shape in the back of Sam's mind, and he swallowed down bile as his cock hardened with the thoughts.

oOo

Morning brought Castiel, and he wasn't alone. The soft sound of displaced air that heralded the god's arrival was immediately offset by the soft grunt of a body hitting the floor. Sam snapped from a half-doze to full awareness in an instant as the scent of another Alpha slammed into him, challenging and raw.

Dean tensed and shoved Sam away and Sam allowed it. He fell back even as all his instincts clambered at him to stay close and stake his claim. Dean pressed back against the wall as though he could melt right through it, his eyes wide with terror and arousal. The faintest hint of Dean's musk, calm through the night, rose to fill the air.

Sam stood up and turned, his bulk blocking Dean from Castiel's sight. The newcomer Alpha had picked himself off the ground and was crouched at Castiel's feet, eyes fixed on Sam, nostrils flaring. Nausea swept through Sam as the other Alpha opened his mouth and growled, but Castiel flicked his eyes toward the man and he fell silent, while his eyes lost their focus. He slumped in place beside Castiel, an empty puppet, and a wave of disquiet swept through Sam at the sight: this was what Castiel wanted to do to his brother.

"Sam," Castiel said. He looked calm, but eagerness underlined his tone, and he was staring at Sam's legs- at what little of Dean was visible.

Sam wanted to stare Castiel down, but his gaze was drawn back again and again to the challenger lying loose limbed at his feet. "Who is that?" Sam asked, voice a low growl of hostility he couldn't contain; it could be passed off as natural hostility, under the circumstances, but he was all-too aware that if he didn't get his impulses under control he was going to out himself, and in the process lose any chance he had at protecting Dean.

Castiel met Sam's eyes evenly, without even a hint of challenge, placid in his unawareness. "He is an Alpha," he said evenly. It was all the explanation Sam got he was restrained again, the chain materializing from the wall to bind him back in his place of forced observance against the wall. Dean, now on full display, stood up from the ground. For all the havoc the unconsummated Heat must have affected him, it didn't show in his movements.

"He won't help you," Dean said. He licked his lips and Sam could imagine how wet he was, how hungry to be filled by whichever of the Alphas got to him first. Sam bit his bottom lip until it bled, the scent of his own blood a welcome distraction. "Not if you want to be the one mated to me."

Castiel smiled, and reached forward to touch Dean's cheek in a gentle caress. "He will not have the chance to even attempt it," Castiel promised softly. His eyes, locked on Dean's, took on the bright glow of soul-fire. Dean wavered in the air and then fell to his knees in a slow, graceful drop. "He will provide me with a service, but he will not touch you without my consent." Castiel smiled. "Unless he wishes to die, of course."

Dean stared up at Castiel with a look of rapture on his face, and Sam realized with a sickening lurch that his brother wasn't home. "Dean!" he called. There was no answer, not even the barest twitch of acknowledgment.

Castiel stripped with the same calm, efficient movements he had once used to purge demons. The Alpha stirred behind him, and with a genteel wave of Castiel's hand, pulled Dean up to face himself. Dean's eyes broke with Castiel's with an almost palpable _pop_ of power, but they didn't regain any of their previous awareness; instead, they sharpened on the Alpha and he tilted his head back in a needy, submissive little whine. Rage tore through Sam at the sight, and he didn't try to fight it. Dean deserved better than this mindless, hormone-driven passivity. At the very least, he deserved a brother who could do something to save him.

The Alpha was focused entirely on Dean, and he stuck his nose under Dean's ear and inhaled deeply. The immediate, competitive scent of another Alpha's musk filled the air and bit at the edges of Sam's thoughts, daring him to interfere. Dean gasped and whined, long and high; Sam could see that his thighs shining and wet.

"Enough," said Castiel. In that moment Sam almost felt an inkling of the worship he knew Castiel craved. Castiel pulled Dean from the Alpha's arms, gently unhooking Dean's fingers from where they had dug into the Alpha's skin, and pressed him to his knees once more. Dean's face was level with the Alpha's groin, and his breathing grew hoarse, like sand in the air; Sam knew without a doubt that the scent would be overpowering, so close. Dean sealed his lips to the fabric over the Alpha's crotch, mouthing at it. Quiet, pleading noises escaped his throat and Sam could only watch. The iron in his mouth was tainted with salt.

"Are you hungry, Dean?" Castiel asked, fingers cradling Dean's head from behind, keeping him in place. "Tell me."

Dean's tongue was bright against the darkening patch of jean on the Alpha's crotch, pink and delicious. "Need to mate," he whispered, absolutely honest. "I can- I can smell him." He closed his eyes and his hands rose up to fumble with the Alpha's buckle. "He's so close..." his voice trailed off as the Alpha's pants fell open. The Alpha's cock nudged its way out of the gap, ruddy and thick. He had a short cock; Sam could already see the swell where his knot would form.

Before Dean could lean forward and seal his lips around the other Alpha's cock, Castiel was there, drawing him back with his grip on Dean's face. Dean made a low, begging sound, reaching his hands forward to keep himself in contact, but Castiel just moved one hand to gather up Dean's, holding them pinned behind his back. Dean struggled, but to no avail, pinned in place by the god's will. "_Please_," he begged, and it was so, so pretty.

Sam forced himself out from his own haze of jealous arousal and turned his attention on the Alpha. The man was frozen, arms raised to touch Dean's face, but stopped mid-motion, still as a statue. Sam could see his eyes, dark with anger, locked on Castiel in a silent, useless struggle of wills.

Castiel hummed tunelessly to himself and moved Dean's body into position. Dean's face dug into the Alpha's groin, the buttons of the man's fly pressing into the curve of his cheek and his nose pressed firmly into the thick skin at the base of the Alpha's cock. He'd lost any semblance of coherency; he was panting, his mouth watering, with a long string of saliva leaking down from the side of his mouth, unnoticed. Castiel spread Dean's knees easily and positioned himself between them, like he belonged there. He clenched his hands on Dean's wrists; they were darkening at the tips and white around Castiel's hands, so tight was his grip. "Dean," Castiel called, gently, and then waited until Dean's eyes regained some of their focus. "What do you want?"

"Mate," Dean sobbed, brokenly. He strained forward and nuzzled into the Alpha's cock, pleadingly.

Castiel nodded, placating. "And how would you get a mate, Dean?"

Dean licked his lips, and then the Alpha's cock when he realized it was in reach. "Need to get fucked," he said dreamily, like he was already imagining it.

"That's right," Castiel said. He was smiling. "Do you want to get fucked, Dean? Be mated?"

"_Yes_," Dean said, his eyes fluttering. His hips were undulating idly, like he could already feel the press of a cock inside him.

"Perfect," Castiel whispered, dragged the damp head of his cock up to Dean's wet, greedy hole in a slow rock. He paused for a moment, then pressed inside, slow and uncompromising.

Dean made a shocked noise of pleasure and bucked, his eyes dark and confused. His arms jerked in Castiel's grip, a desperate bid for freedom. His scent- changed. Where before he had smelt needy, now he smelt.. receptive.

"Shhhhh," Castiel crooned, jerking his hips up in a deliberate bid to hit on Dean's prostate. "Isn't this what you wanted?"

Dean takes a deep breath through his nose and sobs, rubbing his cheek against the string of precome that's dripped from the frozen Alpha's cock. "I don't know," he whispered. It took everything in Sam's power not to thrash against his restraints, but he couldn't keep his own breath even. The other Alpha was shaking just slightly, like an electric current was running through his body.

Castiel smiled and released Dean's wrists; Dean reached one hand back and gripped Castiel's thigh and wrapped the other around the Alpha's waist. He didn't move other than that, frozen between his need to be fucked to mate and the reality of an Alpha in front of him. His cock twitched and a string of precome oozed from it, thick; it dripped slowly to the floor and pooled. It didn't have nearly the same strength of scent as an Alpha's precome, or a Beta's juice, but Sam would given anything at that moment to be able to taste it. His mouth was watering at the thought.

The fantasy came to a crashing halt when Castiel pressed his chest to Dean's back, wiped his hand perfunctorily down the Alpha's cock. then it around Dean to palm at the skin of his belly. He pumped his hips in short, prodding motions; almost idly, he slid his hand up and let it rest just below the arch of Dean's ribs, and pressed his fingertips inside Dean's chest in an all-too-familiar burst of light. The point of contact was too bright to look at, but Sam kept his eyes open and accepted the burn. Dean was shaking, but he didn't seem to be in the same pain as the last time Castiel had done this. His face was twisted up, but the agony writ across it could have stemmed from pain or pleasure both.

"What do you smell, Dean?" Castiel whispered into Dean's ear, so quiet Sam might have missed it if he didn't have his senses so tightly focused on the scene in front of him. He fucked his hips in as he spoke, and Dean puffed out these shocked, breathy pants every time he slid home.

"Smells like- mate," Dean panted out, shaking his head back and forth like he couldn't decide which way to look.

"What do you see, Dean?" Castiel asked, and pressed his fingers more deeply into Dean's chest. The light from Dean's soul was echoed in his eyes.

Dean's eyes fluttered closed and then open and he rolled them up to look at the face of the Alpha whose cock had slicked his face wet. "An Alpha," he said, utterly certain. He licked his lips, and Sam knew he would be able to taste the Alpha there.

"That's right," Castiel praised. He narrowed his eyes and dug his hand in deep, his arm sunk in up to the elbow, but Dean's chest looks completely normal except for that; whereever Castiel's hand was going, it wasn't inside Dean's chest cavity- not really. Dean dropped both his hands to the ground and tipped forward, and Sam could _see_ Castiel sink in just that little bit deeper. "Now, Dean, this is very important: what do you feel, inside?"

Dean was shaking, and sweat was dripping down from his hairline. He was a mess of wetness. With his eyes closed, it was impossible to tell, but Sam could swear he saw tears leaking from his eyes as well. He breathed deep, hitched breaths that sounded like sobs. "I feel a mate," he gasped out at last, voice high and agonized.

Castiel's eyes widened and he smiled, wide, his teeth sharp and dangerous. The Alpha in front of Dean went flying back and slammed against the wall next to Sam with a sick _crack_; he crumpled to the ground and didn't get up. He didn't move his hand from inside Dean's chest, but he used the other one to wrap around Dean's cock in reward. "That's right," he said, victorious. "That's right- that's your mate you're feeling." He slid his eyes shut blissfully and licked a line up Dean's neck, sucking a bruising kiss into the skin just below Dean's ear when he reached it.

Dean eyes drifted open and slid over toward the body of the Alpha. He twitched in Castiel's grip at the sight, pushing back toward Castiel's cock, and Castiel laughed, his joy palpable. "Do you like the feel of your mate inside of you, Dean? Do you want more?"

Dean shuddered in his grip and snapped his gaze from the body to Sam. "Yes," he said. His eyes were heavy on Sam, clear and green. He gave a delighted wriggle and spread his legs wider, the perfect picture of submissive need. "I want more."

Castiel took that for all the permission he needed. He pushed Dean down with one hand on the back of his neck so Dean's ass was raised in the air and slowly, carefully, pulled his arm from Dean's chest as he raised himself up. "You love your mate, don't you, Dean?" he asked, eagerly. He looked victorious, and more than that- happy. He looked so. Fucking. Happy.

Dean shaped his arms into a cradle and buried his face there. "I do," he said. There was no sadness in the sound, nothing to say it was a lie- nothing except the years Sam had spent hearing Dean say _I'm fine_ in that exact same tone of voice.

Castiel shuddered at the words and curled himself around Dean's back, his head dug into Dean's neck. He shuddered, and his hips jerked into Dean in a rapid staccato. His hips eventually stilled, but he stayed curled around Dean, shoulders shaking. He was crying, relieved sobs that wracked his frame.

Dean said nothing. Dean did nothing. Eventually, Castiel composed himself and pushed himself up from Dean's back and withdrew with a wince. "That was not meant to happen," he said. He was looking at Sam, smiling. "I came too soon." He laughed, like it was a joke.

Sam just stared at him. He couldn't look at Dean. He couldn't look at Dean, or this would be ruined.

Castiel sighed, and pressed three fingers into Dean's hole. When he pulled them out they were covered in come, and he hovered his hand beside Dean's head until Dean craned his neck up and began licking it off, kittenlike. Castiel used his other hand to smooth down Dean's hair. "You're perfect," he whispered, like a benediction.

Dean ducked his head away, every indication of shy. Castiel smiled and bent down to press a light kiss to Dean's shoulder. "I will return," he promised, no idle threat. "When I do, I will bestow upon you my children." He nodded to himself, eyes far away as he planned. "They will replace my once brothers and sisters as the new Army of the Lord."

"I've always wanted children," Dean confessed into the skin of his arm. He raised his eyes to Castiel's again. "You won't- you won't hurt Sam, will you?"

Castiel smiled again, smitten. "Your brother will not come to harm," he promised. "He will experience the same protection I give you." He sucked in a sharp, satisfied breath and released it. His expression darkened. "I will not free him," he warned. "I do not wish to hold him in my sway, but he cannot be allowed to hurt you." He splayed his hand out over Dean's back. "Not now."

Dean nodded, half eager, half sad. "Whatever you think is best." He ducked his head again. "Can I stay with him?" he asked, meekly. "He won't understand, but I have to try. He'll listen to me."

Castiel nodded, like he didn't know Sam could hear their _whole fucking conversation_. "Of course, Dean." He closed his eyes and pressed his lips to Dean's in an easy kiss. "I will return with the necessary supplies." He held Dean's gaze for a long second, and then he disappeared.

The moment he was gone, Dean scrambled up from his position and stumbled over to Sam on shaky legs. "We have to work fast," he said, tugging Sam's pants open. "He'll be back soon."

Sam couldn't move his neck, but his hands had no such restrictions. He caught Dean's hands in his own. "Dean," he said. "Getting my pants off won't get me free. What are you doing?" He thought he knew- he was pretty damned sure he knew- but he needed Dean to say it. He wouldn't work from assumptions.

Dean wilted, head ducked low. He inhaled once, bracing himself, and looked up to meet Sam's eyes like he was expecting a fight. He blinked when their eyes met, and fumbled over his words for a moment. "It needs to be you," he said eventually. He broke the eye contact with a blink and looked over at the corpse of the other Alpha, and Sam followed his gaze; there was a smear of red on the wall where his head had impacted with it, and his neck was twisted at an unnatural angle, but his hands- his hands were frozen in the same position they'd been in when Dean can been pressed against him. He hadn't even been allowed to move before Castiel killed him. "I need to mate with someone," Dean said, like it was just another plan. "And I'm not willing to put you at risk. If you're my mate, he won't kill you. Not unless he's willing to let me die, too." Dean smiled, a quick, grim little quirk of his lips. He bit his lips and glanced at Sam through his lashes. Sam shivered at the heat in his eyes, dark with arousal. "You don't- you want it, right?" _Want me?_, Dean didn't ask, but either way, Sam couldn't refuse.

Sam tilted Dean's face up by his chin and waited until Dean stopped trying to avoid him and locked their gazes. "I do," he said quietly. "And even if I didn't want it- want _you_- I would want to mate with you." It was true. Sam would never make Dean face the reality of having his loyalty and soul forcefully get tied up with Castiel's, but the unspoken truth- that he wouldn't have _wanted_ this if not for his own body's transformation and reaction to Dean's Heat. It didn't need to be said: they both knew it. But they'd both been changed, and the urge to mate was there, and it was strong.

Dean smiled at Sam, tentative, and made an abortive move toward Sam's pants again, only to be stopped by Sam's continued grip. "Dean," Sam said.

"_What_, Sammy? We don't have much time, here."

Sam rolled his eyes. "You didn't come," he said. "That's why Castiel didn't mate with you, isn't it?"

Dean blinked. "As far as I can figure," he said. He made another move toward Sam's pants.

Sam shook him. "So _think_ Dean. All I need to do is make you come. Right?"

Dean tilted his head, considering. "It's the only thing Castiel couldn't do," he agreed, slowly. His eyes sharpened on Sam. "Just what are you thinking?"

Sam let his eyes trail down Dean's chest to his cock, thick and full this whole time, temptingly dark against the pale skin of Dean's belly. "I blow you," he said, and cleared his throat. "You're in heat, so it shouldn't take long. That way we won't have to- you know." He waved down at his own cock in explanation. It killed him to make the offer; Dean's scent was thick on the air, his slick spread around Sam's jeans, but if Dean wanted a way out, he was going to give it to him, even if it killed him.

Dean smacked Sam on the head. "We're only going to get one chance at this, Sammy. I'm not going to toe the moral line." He sucked in a long breath and closed his eyes, and Sam _knew_ the shudder that wracked through Dean's body was because he could smell Sam, Sam and not anyone else. "If you think I won't come on your cock, you're dreaming," he husked out, and a shudder wracked his body. Blood flushed to the surface of his skin, his temperature rose, his body just- begging for it.

It was all the excuse Sam needed, Dean's words the ultimate justification to give in to his own wants. Fuck nice. Fuck _right_. Dean was his, by blood and soon by more than that. Sam grabbed a hold of Dean's hips and dragged him down, so Dean was perched on his lap, legs splayed out to either side. He couldn't lean back to make the position easier for Dean- his back was still pressed tight to the wall, locked in place by the collar around his neck- but he strained forward as far as he could even as he tangled one hand in Dean's hair and dragged him forward into a kiss.

Dean opened to it eagerly, hunching in so he could grip at Sam's shoulders. He couldn't wrap his arms around Sam, but he curled himself in so they were pressed together awkwardly at their hips and shoulders. Sam pushed his way into Dean's mouth and Dean was there, touching the tip of his tongue's to Sam's when it fucked past the barrier of Dean's teeth. Dean's scent changed, subtly, and for the first time it felt focused on Sam. He could _taste_ Dean's body chemistry shifting as they kissed, into something claimed, owned, _Sam's_. He wrapped one hand around Dean's waist and held him close, the heat from Dean's body undeniable, inescapable.

Dean broke the kiss and pushed just slightly onto his knees, so his cock rubbed against the hollow of Sam's abs. He arched back and bit his lip as he went, like the world's hottest lapdance. Sam put his hands on Dean's hips, running a finger along the dip of his waist, then moved his hands around to cup the cheeks of Dean's ass in his hands, pulling them apart just a little. Dean's scent was intoxicating, but underneath it Sam could smell Castiel on him, _in him_, a trespass that couldn't be tolerated.

"Turn around," Sam growled out, and didn't wait for Dean to obey, just pushed him onto his feet and then flipped him around. Sam hated his collar, hated the lack of freedom to claim Dean how he wanted to, the way Dean needed. He wanted to push Dean down on the ground and fuck him into the dirt, wanted to rest on his back and watch Dean ride his knot, wanted to make Dean fall apart. There would never be enough time for Sam to do all the things he wanted to do to Dean.

Sam spread Dean out wide over his lap again, this time with Dean's back to his front. "When we get out of here," he promised, "I'm going to spend hours eating you out." He pushed two fingers roughly into Dean's hole and curled them in, then out, digging out any traces of Castiel's come. "I'll just fucking- go to town. Lick you till you're not dripping with anything but _me_, my spit. I'll suck your own juice right out of you. Fill you up with my come to replace it." He wiped his fingers on his pants angrily and tilted Dean's hips back toward him. "You want that, Dean?"

Dean shuddered in his lap and twisted his neck to look at Sam over his shoulder. "Yeah," he husked. "I just wanna be- drenched in your come. Stink of you, so everyone knows I'm your's." He swallowed, his Adam's apple bobbing wildy. His breath hitched when Sam curled his first around Dean's cock and squeezed, and Sam smiled at the exhausted little sound of pleasure he made at the touch.

Sam didn't waste any more time. He tilted Dean's hips back and gripped his own cock at the base, pressing harder with his thumb so it swung down just enough to touch on the crease of Dean's ass, then further down, into the red, swollen center of his hole. Dean was clearly in Heat; his hole was swollen and puffy, shiny with his own slick. Sam didn't want to think about the fact that some of the swelling might have been from Castiel's cock fucking his brother. There was no tell-tale white Sam could see, but even the thought of it, the thought of someone else's spunk filling Dean and trying to take him from Sam made the rough, claiming instincts rise up inside of him. He pressed the crown of his cock to Dean's hole and it was soft, welcoming; the muscle just spread apart for him like it wanted Sam inside, a hungry mouth waiting to be fed.

Sam was more than willing to oblige. With one smooth, quick motion, he snapped his hips up and pulled Dean down, gravity helping the motion, so Dean slid all the way down his cock in one go.

That was all it took for Dean to come all over Sam's fingers. "Fuck!" Dean yelled, and the smooth, welcoming heat of his ass clamped down on Sam's cock, rhythmic contractions that matched the bursts of fluid from his cock. Sam shuddered underneath him and smeared the mess from Dean's cock over his hand, gathering it up so his whole hand was covered in it.

"There we go," Sam whispered, victorious. "That's what you needed, huh? A real Alpha staking his claim." He removed his hand from Dean's cock and raised his hand to dangle in front of Dean's face. "Taste yourself," he ordered calmly.

Dean stretched his neck forward and sealed his lips to Sam's palm, sucking hard, gathering up the come and using the force of his mouth to draw Sam's hand into easier range of his mouth. Sam groaned and bucked his hips up into Dean and pushed four of his fingers into Dean's mouth, and Dean just took it in, opened wide for it like he couldn't get enough. Sam's slid his fingers along Dean's tongue and just let them rest there as Dean sucked and swallowed around them, gathering up all the traces of his own come.

Sam shiverred, and heat pools at the base of his spine. He wants to make this last, but it's more important that he knot Dean; more important to make _certain_ the mating takes, that Dean gets claimed by him so Castiel can't touch him. He had to get his knot into Dean.

Dean's tongue pushed against Sam's fingers, forcing them out, and Sam withdraws them reluctantly. "You gonna fuck me or what?" he asked, his voice fucked out like Sam's cock had been in his throat rather than his fingers.

Sam's cock twitched and his head spun as more blood was flushed to it, too quickly. Sam shifted so his arms bracketed Dean, cradling Dean on his lap. He tucked his head into Dean's neck and moved his hands down, underneath Dean's legs. The he picked Dean up, the weight a burning strain on his arms, the air almost frigid on the wet skin of his cock and jerked him back down, hard, and rolled Dean's hips around in a tight circle to help pump his knot up to full size.

The feeling of Sam's knot swelling was- strange. He'd never experienced it as himself before, and the hazy memories from his exploits without a soul don't feel _his_ enough to point to them as experience. It started with an itch at the base of his cock and grinding up into Dean's ass made it feel better, but it wasn't _enough_. The feeling just built and spread, until the whole of his cock was a throbbing point of _need_.

"Dean," Sam whispered, and groped for Dean's hand, curling his own around it. "I don't- _shit_." His knot was swelling up fast, and Sam held Dean close, terrified of what would happen if he slipped out of his brother's body. He shivered and wrapped himself more firmly around Dean. "Does it hurt?" he said, because Dean wasn't, he wasn't moving.

Dean said nothing, but he brought their twined hands down to his cock, which was hard again, the shaft hot and the head even hotter, drooling out fluid at an almost shocking rate. "You're- your knot's pressed right against my prostate," Dean managed to gasp out, and the words bit out like they pained him. He keened and arched back, grinding down on Sam's lap. "Doesn't hurt."

Sam moaned and fucked up into the slick grasp of Dean's body, and Dean spread himself wide, wider, and with a sharp little twist of Dean's hips, Sam hit- hit something different. It was a patch of roughness in the midst of the world tight, wet velvet that was Dean's ass, and the feel of his cock rubbing against it sent stars shooting off in Sam's vision. Every time he hit it, Dean let out a little scream. He'd started to struggle, but not to get away- he gripped Sam's knees so hard it hurt and used his grip to raise himself up and fuck back harder, trying to get Sam deeper.

"Sammy," he whined, desperate, and then froze. His ass clamped down and he was coming in Sam's lap again, and as his muscles contracted that rough, hot little spot inside of him... moved. It seemed to suck at Sam's cock, begging him to come. A wave of pleasure rolled over Sam and he pressed a hand against Dean's lower belly, and bit down on Dean's shoulder as he did, just like Dean wanted, and came.

It didn't make him want to stop fucking.

His come added to the wet mess that was Dean's ass, but his knot was full, keeping it all trapped inside, so Sam was sliding around in their combined juices. "Fuck, Dean," he grit out, shaking sweat out of his eyes, "All I can think about is getting you pregnant."

Dean froze on his lap and again his body contracted in orgasm, milking Sam, and all Sam could think of was a video he'd seen in Sex Ed, of a woman's cervix contracting in orgasm, gathering up the come to feed it into her womb. He growled and bit down on Dean's neck, then tucked his teeth behind his lips and started to suck. He wanted Dean marked, by sight and scent and taste, so no one would ever even be able to _think_ of breeding with him again. He was Sam's. _Sam's_ "You're mine," he snarled as he tore his mouth from Dean's skin. "Say it."

"Your's," Dean moaned out, shuddering all around Sam, on him, wrapped up so deep in Sam they'd never be apart. "Love you, your's, _Sammy_." His body contracted again in a small, weak attempt at a third orgasm, and Sam rocked his hips up in a gentle motion, still pumping his own come into his brother.

Gradually, the movement of their bodies slowed. Dean's legs were still spread out over Sam's, but he twisted so he was tucked in close to Sam's chest, resting his cheek against Sam's. Sam realized dimly that they were both drenched in sweat, and he shiverred, cold everywhere except where Dean was touching him. His cock was still pumping come into Dean, and he hoped with grim determination that Dean would catch, would swell up with a child that would be their's, so Castiel could never delude himself into thinking he could have something that wasn't his.

He only realized that his eyes had drifted closed when he opens them again and there, over Dean's shoulder, was Castiel.


	4. Epilogue

Castiel should have known better. He tracked the development of the Winchester family, saw their founding members copulate and bond, had gone back in time and traced their genesis back to the scarred, crafty apes they had grown from. He watched as these brothers spat in God's plan and escape from the threads of destiny.

Every time someone tried to tear them apart, they just grew more tangled with each other, closer to one being.

Castiel is not his father. He never should have dreamed that he would be able to do what his father could not- tear apart Sam and Dean Winchester, bring Dean into _his_ alliance, loyal to him before he was loyal to Sam.

He appeared in the cell in which they'd placed him, giddy with his victory, the harness and knot-attachment he'd found at a particularly decadent shop of lustful wares. The molecules of Dean's Heat clung to him, and the Alphas inside the building had turned toward Castiel's invisible presence, confused as they searched out the source.

Dean was on Sam's lap, impaled on his cock. When Castiel looks closely, he can see the small, bright flare of life developing inside of him.

It was the ultimate betrayal, the final line drawn in the sand. Dean was not his. Dean was not _meant_ to be his.

The roar at the back of Castiel's mind grew, demanding he punish the Winchesters, demanding blood. He took in Dean's expression of defiance, Sam's possessive, hateful stare, and closed his eyes.

Wound the clock back.

He could feel the dissolution of the mating bond, could feel the horror and rage return to the room as it flicked back through the rapes he can committed on Dean's body. He could feel, now that he was looking for it, Sam's horrified, aroused intent, focused on Dean with the natural attraction of an Alpha. He kept going backwards, until he reached the warehouse where his new life as a god had begun.

He steps into himself, superimposed over the other, and opened his eyes.

"I'm your new God," he said, for the second time, for the first time. "Bow down and profess your love unto me."

He would not make the same mistake twice.

Fin.

A/N: I would love to hear your thoughts.


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